Attachment for sewing machines



Marsh 27, 1934. J. D. KARLE ATTACHMENT FOR SEWING MACHINES Filed Feb. l5, 1933 2 Sheets-Sheet. l

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ATTACHMENT FOR .SEWING MACHINES Filed Feb. 15, 1953 2 Shelebs--Sheet 2 Patented Mar. 2.7, 1934 vUNITED STATES ATTACHMENT FOR SEWING MACHINES John D. Karle, Roselle Park, N. J., assigner to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Application February 15, 1933, serial No. 656,810 v 7 claims; (cl. 164-175) This invention relates to improvements in trimming or cutting devices and more particularly to a pinking cutter which may be readily attached to the usual type sewing machine so as to be operated thereby. 1

Figure l is a front elevation of my improved pinking attachment showing it applied to a sewing machine of the usual type.

Figure 2 is a side elevation taken from the right hand side of Figure 1.

Figure 3 is a side elevation taken from the left hand side of Figure l.

Figure 4 is a cross-sectional View taken substantially along the line 4 4 of Figure 1.

15 Figure 5 away, to show the construction of the platen roller and its relation to the cutting element.

In the embodiment of this invention selected for illustration 1 is the base of the attachment which rests upon the cloth-plate 2 of the sewing machine. Located above and made integral with the base 1 is a frame 3 provided with a projection 3' formed with a notch 4 (Fig. 4) adapted to receive the usual spring-pressed presser-bar 5 25 of the sewing machine. A screw 6 extending through the projection and threaded into the presser-bar rigidly secures the attachment to the presser-bar.

Pivotally secured on the extension 7 of the housing 3 by the pivot 8 is a needle-bar actuated lever 9 having its forward end bifurcated to receive the usual needle-clamp 10 carried by the reciprocating needle-bar 11 jurnaled in suitable bearings in the usual hollow head 11 of the sew- 35 ing machine. Pvoted at 12 to the rear end of the lever 9 is a pawl 13 urged downwardly by a coiled spring 14 into engagement with the ratchet-wheel 15 which is free to rotate on the pivotpin 8.

Conjoined to the ratchet-Wheel 15 is a spur gear 16 meshing with an intermediate gear 17 journaled on the pivot-stud 18. The intermediate gear 17 meshes with a larger spur gear 19 keyed to one end of a shaft 20 which is journaled 45- in the long bearing boss 21. A rotary cutting element 22 is fixed to the other end of the shaft and rotates therewith. To prevent injury to the operator when the attachment is being operated there is secured to the bearing boss 21, by the screw 23 a guard-member 24 for the cutting element 22.

Mounted below the cutting element and supported by the frame 3 is a work-supporting plate 425 provided with a suitable opening 25' (Fig. 5)

= through which the outer periphery of the roller is a perspective View, partly broken bearing indicated generally as 26, extends. The roller 26 cooperates with the cutting wheel 22 for severing the material and as illustrated it comprises an outer case-hardened race-member27 and an inner race-member 28 betweenwhich are 60 interposed the balls 29. Disks 30 are providedA for retaining grease in` the raceway and also to4 prevent foreign matter from entering the bearing. Y f

The roller bearing 26 is of standard form and 65' the inner race-member 28 is supported inany suitable manner as, for example, by being secured to the reduced and offset end 3l of a shaft or stud 32 by a driving iit. The shaft 32 is journaled in the split bearing boss 33 and is normally clamped 70 against rotation by a screw 34 which tightens the split bearing boss 33 about the shaft 32.

' In the operation of the attachment the reciproeating needle-barvoscillates the lever 9 'which' n, causes the pawl 13'to impart a step by step r'o- 75 tary motion to the ratchet-wheel 15 and spur gear 16. This rotary motion is imparted to the cutting element 22 through the gears 17 and 19 and the shaft 20. The cutting element 22 cooperatively engages or is pressed against the platen wheel 26 and the friction causes the outer racemember 27 to rotate. To compensate for wear and to vary the pressure between the cutting element 22 and the platen roller 26, the screw 34 is loosened to allow the split hub 33 to expand suf- 85 iciently to permit rotation of the shaft 32. The offset end 31 of the shaft is provided with a nick 36 into which the end of a flat implement such as a screw driver may be inserted to facilitate the adjustment.

It will be observed that my improved attachment is located to the left of the hollow head in which the needle-bar and presser-bar are journaled. This location gives access to the attachment and permits the material to be placed in and fed through the attachment without interference from the stitch-forming mechanism or the standard and bracket-arm.

Having thus set forth the nature of my invenc tion what I desire to secure by Letters Patent is:-- 100 1. A pinking attachment for a sewing machine having a hollow head in which a reciprocating needle-bar and a presser-bar are journaled, comprising a frame, adapted to be secured to the presser-bar of the machine, a lever carrying a pawl and actuated by the needle-bar, a ratchet actuated by said pawl, a shaft, a train of gears connecting said ratchet-wheel with said shaft,

a rotary cutting wheel carried by said shaft, a platen roller carried on a horizontal pivot and cooperating with said rotary' cutter and means for adjusting said platen roller relative to said cutting wheel.

2. A pinking attachment for a sewing machine having a work-supporting plate and a hollow head in which a reciprocating needle-bar and a presser-bar are journaled comprising, a frame, means for securing said frame to said presserbar, a shaft journaledin said frame, a rotary cutting wheel secured to said shaft, driving mechanism actuated by the needle-bar for operating said shaft, a stud carried by said frame, a platen roller rotatably carried on said stud, and a clothplate carried by said frame and having an opening through which said platen roller extends, said cloth-plate being disposed above and extending over the edge of the work-supporting plate of the machine. i

3. A pinking mechanism comprising, a frame, a cutter rotatably supported by said frame, a supporting element carried by said frame, and a platen roller carried by said element, said platen roller having an outer race-member the outer periphery of which coacts with said cutting wheel, an inner race-member anda series of balls interposed between said race-members.

fi. The combination with a conventional ballbearing having inner and outer race-members and a series of anti-frictional elements between said members, the outer member having a cylindrical outer surface, of a frame including a worksupporting plate having an aperture, a stud mounted below said plate and carryingsaid inner race-member in a position for the upper portion of the outer cylindrical surface of the outer race-member to be exposed through said aperture, a circular cutting element .mounted on said frame to cooperatively engage said exposed upper portion of said outer race-member, and means for driving said cutting element.

5. A pinking attachment for a sewing machine comprising, in combination, a frame, an adjustable stud. carried by said frame, an anti-frictional bearing carried by said stud, said bearing having an outer race-member formed with a cylindrical outer surface, an inner race-member, a series of anti-frictional elements interposed between said members, a shaft carried by said frame, a cutting element carried by said shaft and coacting with the outer cylindrical surface of said outer racemember, and driving mechanism actuated by the machine for rotating said cutting element.

6. In combination, a frame, a shaft journaled in said frame, a cutting element Xed to said shaft, driving mechanism for actuating said cutting element, a stud carried by said frame, a cylindrical anti-.frictional bearing fixed on said stud, said bearing comprising an outer racemember having its cylindrical outer surface coacting with said cutting wheel, an inner race member, a series of anti-frictional elements interposed betweenY said members and means for relatively adjusting the position of the anti-frictional bearing and the cutting element.

7 A pinking attachment for a sewing machine having a hollow head in which a reciprocating needle-bar and presser-bar are journaled, comprising a frame adapted to be secured to the presser-bar of the machine, a lever actuated by said needle-bar, a ratchet wheel actuated by said lever, a shaft, a train of gears connecting said ratchet wheel with said shaft, a rotary cutting wheel carried by said shaft, a platen roller carried on an adjustable horizontal stud, said platen roller comprising an inner race-member which is fixed to the stud, an outer race-member which cooperates directly with the rotary cutter, and antifrictional elements interposed between said race-members.

J OHN D. KARLE. 

